Scoring and breaking apparatus for vitreous tubing



Jan. 16, 1962 J. A. LUTZ ETAL 3,016,654

SCORING AND BREAKING APPARATUS FOR VITREOUS TUBING Filed March 27, 1958 2 Sheets-Sheet 1.

lnven tcvs: John [XLUTZ Francis JVIciovwi by 0% Jan. 16, 1962 J. A. LUTZ ETAL 3,

SCORING AND BREAKING APPARATUS FOR VITREOUS TUBING Filed March 27, 1958 2 Sheets-Sheet 2 lnv n t'ovs: John A.Lutz Ffancis LIA/idem, b5 0% id Theiv A t ovneg.

United States Patent 3,016,654 SCORiNG AND BREAKING APPARATUS FOR VITREOUS TUBENG John A. Lutz and Francis J. Vidoni, Bridgeville, Pa., as-

signors to General Electric Company, a corporation of New York Filed Mar. 27, 1958, Ser. No. 724,353 2 Claims. (Cl. 49-48) The present invention relates to methods and machines for subdividing lengths of vitreous tubing and solid cylindrical vitreous rods and its principal object is to provide a compact high-speed machine of simple structure requiring a minimum of maintenance for accurately subdividing lengths of vitreous tubing and solid cylindrical vitreous rods to predetermined lengths having square-cut ends requiring no subsequent end trimming.

Another object of the invention is to provide an effective method of subdividing lengths of vitreous tubing and cylindrical vitreous rods. Further objects and advantages of the invention will appear from the accompanying drawing, the following description thereof, and from the appended claims.

In accordance with these objects, the method of the invention comprises the step of scoring the lengths of tubing or the rods along a continuous circumferential line while applying a bending moment'to the'portion of the tubing or rod being scored and gradually increasing the magnitude of the applied bending moment as the angular distance of the score line around the tubing or rod increases until the tubing'or rod breaks at the score line.

A machine embodying the invention comprises a conveyor for carrying lengths of tubing or rods along a predetermined path generally transverse to the longitudinal axes of the tubing or rod with the lengths of tubing or rod free to rotate on their axes in the conveyor, a knife having a straight cutting edge mounted on one side of the path and normal to the axes of the conveyed tubing, and means mounted on the opposite side of the path for rolling the tubing alongthe knife edge. The knife and the rolling means are constructed and arranged to apply' a bending moment of increasing magnitude to the tubing or rod as these are rolled along the knife edge to score the tubing or rod along a continuous circumferential line and break the tubing or rod at the score line. In certain instances, described hereinafter, additional means for increasing the magnitude of the bending moment applied to the tubing or rod by the machine are also provided.

In the drawings accompanying and forming part of this specification two species of machines embodying the irivention are shown, in which FIG. 1 is a top plan view invention.

FIG. 2 is a front elevational, partly sectional view of the machine shown in FIG. 1.

FIG. 3 is a fragmentary plan View, partly in section, of part of the machine shown in FIGS. 1 and 2.

FIG. 4 is a schematic representation of a mechanism embodying the invention shown in side elevation, and

FIG. 5 is a similar representation of the mechanism shown in FIG. 1 and in a sectional view taken along the line 55 of FIG. 4.

The machine shown in FIGS. 1-3 of the drawings comprises a support in the form of an open housing 1 having pairs of horizontal cross members 2, 3 and 4, 5 for supporting other components of the machine. The

of a machine embodying the lengths of vitreous tubing or solid cylindrical vitreous,

rods 6 to be subdivided by the machine are inserted at the open top of the housing support 1 into the conveyor means including the sleeves 7 for carrying the rods of the 3,016,654 Patented Jan. 16, 1962 tubing 6 in a horizontal circular path while supporting them in a vertical position.

The sleeves 7 of the conveyor support. the rods or the tubing 6 substantially in a vertical position and loosely engage the rods or the lengths of tubing so that they may rotate on their longitudinal axes and move downward under the force of gravity as described below. Lengths of tubing have been shown in the drawing and are referred to hereinafter as tubes 6 for convenience. It will be understood that the following description applies also to solid cylindrical rods unless stated otherwise.

The vertical sleeves 7 are atfixed to the circular sup port plate 8 by chucks 9 bolted to the plate and holding the sleeves in a circle concentric with the center of the plate 8. The plate is keyed to a vertical shaft 10 which is supported by the cross members 4 and 5 of the housing 1 and is rotated through the gear 11 keyed to the shaft Ill, the gear 12 engaging gear 11, the shaft 13 supported by cross members 2 and 3 and to which gear 12 is keyed, the wheel 14 keyed to the shaft. 13 and the belt 15 engaging the wheel 14 and the pulley of an electric motor drive (not shown).

The conveyor when driven by the above-described apparatus carries the tubes 6 in sequence to a cutter means for scoring the tubes. The cutter is constituted by a stationary knife 16, preferably of Carboloy, cemented tungsten carbide, having a straight cutting edge 17 presented to the outer side of the conveyed tubes 6. The knife is mounted on a bracket 18 attached to the support housing 1 with the edge 17 of the knife transverse to the axes of the tubes 6.

The conveyed tubes 6 presented to the knife edge 17 are scored by being rolled along and pressed against the edge 17 by roller means including the wheel 19. The wheel 19 is equipped with a rim 20 of resilient friction material, such as a ring of soft rubber afiixed to the wheel. The wheel rim 20 is opposed to the knife edge 17, is spaced therefrom a distance less than the outer diameter of the tubes 6 and engages the inner sides of the conveyed tubes 6. During operation of the machine, wheel 19 is rotated in the same direction as the chuck plate 8 of the conveyor but at a higher speed to avoid slippage between the tubes 6 and the knife edge 17 on one hand and between the tubes 6 and the rim 20 on the other hand. Wear on the knife edge 17 and the rim 20 thus is minimized during operation of the machine.

The wheel 19 is rotated by the hollow shaft 21 which is coaxial with the shaft 10 and is supported by the cross members 4 and 5. The drive for the shaft 21 includes gears 22 and 23 keyed to the shafts 21 and 13, respectively.

A stationary breaker arm 24 for the scored tube 6 is mounted on one of the brackets 25 bolted to the support 1. The lower ends of the tubes 6, while the tubes are being conveyed as described above, rest on the helical slide 26, part of which has been broken away in FIG. 2, mounted on the brackets 25. The slide 26 prevents the loosely held tubes 6 from dropping out of the sleeves 7 of the conveyor and terminates in a lower horizontal portion 27 beneath the knife 16. The chute 28 extending outward in a downward direction from beneath the knife 16 and the breaker arm 24 is secured by brackets 29 to In the operation of the machine the'tubes 6 are inserted by hand in the sleeves 7 and are lowered upon the helical slide 26. The drive for the machine is then energized to rotate the shaft 10 and the shaft 21 for the conveyor and the wheel 19, respectively, in a clockwise direction. The tubes 6 are thus carried in a circular path and brought in sequence into engagement with both;

the knife edge 17 and the rim 20 of the wheel 19 with the lower ends thereof resting on the horizontal part 27 of the slide 26. The distance between the knife edge 17 and the slide part 27 determines the length of the portions separated from the tubes 6.

As clearly illustrated in FIG. 3, the knife edge 17 intersects the circular path followed by the conveyed tubes 6. In FIG. 3, the various positions of a single tube 6 are indicated by dotted lines as the tube is rolled along the knife edge 17 toward the breaker arm 24. The knife edge 17 thus is a chord of the circle which the outer sides of the conveyed tubes 6 would define except for the interception of the path by the knife edge 17.

In accordance with the present invention the diameter of the wheel including the rim 20, the outer diameter of the tubes 6, the thickness of the resilient rim 20 of the wheel 19 and the distance between the knife edge 17 and the rim 20 of the wheel are correlated that the tubes are rolled along and pressed against the knife edge an angular distance of 360 and more around the circumference of the tubes as they are carried into the narrowest part of the gap between the knife edge 17 and the rim 20. The rim 20 extends above and below the level of the knife edge 17 and tends to bend the portions of the tubes 6 engaged thereby over the knife edge 17.

As the tubes 6 thus conveyed and rolled, a bending strain or moment is applied to the tubes as they are being scored and the bending moment is increased as the angular distance of the score line around the tube is increased. With tubes 6 of soft glasses, that is, low softening temperature, high coefficient of expansion glasses, such as commercial lime or lead glasses, the bending moment applied to the tubes by the rim 20 and the knife 16 is sufficient to cause the tubes to break cleanly at the score line to provide short lengths of tubes having square cut ends requiring no end trimming. When subdividing lengths of soft glass tubes the breaker arm thus is not necessary and may be omitted, when desired.

It has been found desirable, however, to provide a breaker arm 24 when tubes of hard glasses, or quartz, are subdivided by the machine. Hard glasses are those having a high softening temperature and a low coeflicient of expansion, such as commercial borosilicate glasses. The breaker arm 24, when included in the machine, is mounted about half-way between the horizontal portion 27 of the slide 26 and the edge 17 of the knife 16 and presents a cam surface 30 to the conveyed tubes. The cam surface 30 is straight and extends part way across the path of travel of the tubes 6 as the latter are rolled along the straight knife edge 17. As shown in FIG. 3, the cam surface starts at a point located just beyond the narrowest part of the gap between the knife edge 17 and the rim 20 in the direction of travel of the wheel 19 and inward of the inner sides of the conveyed tubes 6.

The arm 24 cooperates with the sleeves 7 and the knife edge 17 to increase the bending moment applied to the conveyed tubes 6 by the rim 2t and the knife 17. This arrangement of machine parts is effective for cleanly breaking at the score line tubes 6 of hard glass and quartz and may be utilized as well for soft glass tubes, but is not usually necessary for use with soft glass tubes. Whether the breaker arm is included or omitted from the machine, the knife 17 serves both as a means for scoring the tubes 6 and as a fulcrum or an anvil for applying a bending moment to the tubes 6 to simplify the structure of the machine.

For subdividing lengths of hard glass tubing having an outer diameter of one-quarter of an inch, a length of about two feet ,or more into lengths of six inches, a wheel 19 ten inches in diameter having a soft rubber rim onequarter of an inch in thickness and one inch in width with the knife edge -17 mounted about one-eight of an inch or slightly less from the periphery of the rim is effective. The wheel 19 is rotated in a clockwise direction at about twice the, speed of rotation of the chuck plate 18 by the gear train and the drive means described above. The tubes 6 of this diameter are rolled along the straight edge of the knife for an angular distance of 360 or more before engaging the cam surface of the breaker arm and break cleanly at the score line. The lower sections of the tubes broken off as described drop down on the chute 28 and travel out of the machine by gravity. The parts of the conveyed tubes remaining in the machine drop in the sleeves by gravity until their lower ends rest on the slide 26 and are again carried around the wheel 19 by the conveyor to again be severed as described above. This operation is repeated until all the tubes have been subdivided throughout their entire length. Soft glass tubing of the same outer diameter may be subdivided as described above with the breaker arm 24 omitted.

For subdividing soft glass tubes having an outer diameter of 0.062 inch the parts of the machine are modified. For tubes of this diameter a wheel 19 four inches in diameter is effecive for rolling the tubes a sufficient distance along the knife edge 17. In the modified machine the size of the other parts thereof are reduced correspondingly, the rim 20 is preferably the same in thickness and in width as the rim 20* described above for the ten-inch diameter wheel. The wheel and the conveyor are driven in a clockwise direction with the speed of the wheel being approximately twice the speed of the conveyor. The knife edge 17 is spaced from the periphery of the rim 20 a distance equal to or slightly less than one-half the diameter of the glass tubes.

As pointed out above, the breaker arm 24 may be omitted from the machine when subdividing soft glass tubes. The machine is capable of subdividing soft glass tubes of this diameter into lengths of only 0.080 inch. When such lengths are separated from the tubes the horizontal portion 27 of the slide 26 and the edge 17 of the knife are separated this distance apart with the slide portion 27 as close to the lower edge of the rim 20 as possible so as to have the resilient rim 20 extend above and below the level of the knife edge 17 so that a bending moment of increasing magnitude is applied to the portion of the glass tube being scored.

Solid cylindrical rods of soft glass having an outer diameter 0.015 to 0.020 inch also may be subidivided by the machine modified as described in the preceding paragraph.

The mechanism illustrated in FIGS. 4 and 5 is a simplified embodiment of the invention and comprises a horizontal support 31 having a straight guideway consisting of two parallel rails 32 and 33 for guiding the sliding block 34 which is mounted between and engages the rails and is movable along the guideway. Four rollers 35, 36, 37 and 38 are mounted on the block 34 with. the axis of rotation of each roller transverse to the direction of travel. of the block 34 along the guideway. The rollers are mounted in pairs 35, 36 and 37, 38 with the rollers in each pair aligned with but spaced from the corresponding rollers in the opposite pair and the rollers in each of the respective pairs spaced apart sufficiently to provide a trough for the tube 6 to be subdivided. The tube 6 thus is supported by the rollers at two longitudinally spaced apart parts thereof and in a position transverse to the direction of travel of the slide block 34. A guide bar 39 in the form of an angle iron is mounted on the support 31 parallel with but spaced from the guideway to prevent the tube from shifting laterally of the path of travel of the slide block 34.

The mechanism also includes a straight-edged knife 40 for scoring the tube 6 supported by the rollers on the slide block. The knife is mounted above the rollers with the straight cutting edge 41 thereof in a vertical plane located between the pairs of rollers and the knife extends along the path of movement of the supported tube 6. The knife is mounted on an arm 43 pivoted at one end for movement in a vertical plane on the end of the vertical support 44 aflixed to the main support 31 of the mechanism at the far end of the path of travel of the block 34 in the guideway. The horizontal pivotal axis of the arm 43 is indicated at E5. The opposite end of the arm is urged downward toward the main support 31 by the compression spring 46 mounted on the threaded bolt 47 which passes through a longitudinally extending slot 48 in the arm 43 and is threaded into the main support 31 and held by the lock nut 49, as shown in FIG. 4. The spring 46 presses against the nut 51 affixed to the upper end of the bolt 47 and against the pivoted arm 43 to urge the knife edge 41 against the tube 6 supported on the rollers 35 to 38. Washers 52 and 53 are provided between the spring 46 and the nut 51 and the arm 43. The knife 4%} is clamped between the blocks 54 and 55 aifixed to the arm 43. Stop nuts 56 and '7 are threaded on the bolt 47 for limiting the downward movement of the knife 40.

The tube 6 is placed on the rollers 34 with one end thereof against the guide bar 39 and with the slide block 34 positioned near the end of the knife 4% remote from the pivot 45 of the arm 43. The knife 40 is then lowered until the edge 41 rests on the tube 6. The knife edge 41 is pressed against the tube 6 by the spring pressed arm 43. The slide block 34 is then moved forward along the guideway in the direction of the arrow.

The forward movement of the block under the knife results in the tube 6 being rolled along the knife edge 41 and being scored along a continuous circumferential line transverse to the tube axis while the tube 6 is subjected to a bending moment which increases in strength as the tube is carried in the direction of the support 44 as indicated by the arrow. The knife edge 41 preferably slopes downward in the direction of the support 44, as shown in FIG. 4, to further increase the bending moment.

The force exerted by the spring 46 may be adjusted by turning the nut 51 on the threaded bolt 47. The force should be suflicient to score the tube 6 without crushing it. This can be determined readily by the operator for different tubes of various wall thicknesses, diameters and physical characteristics and for quartz, hard glass, or soft glass rods or tubes.

It is not essential that the tubes be scored a full 360 around their circumference though it has been found desirable to roll the tubes along the edge of the knife of the machine illustrated in FIGS. 13 a distance such that the tubes make at least one full turn on their axes while in contact with the knife edge 17. This assures scoring the tubes circumferentially for an angular distance sufficient to cause the tubes to snap or break at the score line under the increasing bending moment applied to the tubes individually and in sequence by the machine during operation. The score line is light as the tubes start to roll along the knife edge and becomes increasingly heavy as the tubes progress therealong toward the narrowest part of the gap between the knife edge 17 and the wheel rim 24). As has been demonstrated by the mechanism illustrated in FIGS. 4 and 5, the tubes will snap or break at the score line under an increasing bending moment having a minimum strength sufficient to score the tubes and a maximum strength insuificient to crush the tubes after the tubes have been scored an angular distance greater than 180 and less than 360. Usually the tubes will snap after being scored circumferentially for an angular distance of 270.

In the appended claims the length or lengths of vitreous tubing and the solid cylindrical vitreous rod or rods subdivided by the method and the apparatus of the invention have been designated generically as cane or canes.

While two embodiments of the invention have been shown and described, it will be understood that changes in the form and details of the devices illustrated may be made by those skilled in the art without departure from the scope of the invention as defined in the appended claims.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A machine for subdividing vitreous canes comprising in combination, means for conveying a plurality of canes in parallel spaced positions along a curvilinear path while supporting the canes for rotation on their longitudinal axes, cutter means on one side of said path presenting to the conveyed canes a stationary straight cutting edge intersecting said path in a plane normal to the axes of the conveyed canes, means including a wheel mounted on the opposite side of said path for engaging and rolling the conveyed canes along said cutting edge, the periphery of said wheel being opposed to and spaced from said cutting edge a distance less than the outer diameter of the conveyed canes, said wheel being stifily resilient at its peripheral portion and being mounted for rotation on an axis parallel with the axes of the conveyed canes, the stiffly resilient peripheral portion of said wheel extending parallel with the axes of the conveyed canes so as to engage the said canes for a substantial distance longitudinally of the canes, said cutting edge being positioned to engage the conveyed canes intermediate the ends of the longitudinally extending portions of the canes engaged by the stifily resilient peripheral portion of said wheel, said machine comprising also means for driving said conveyor and for rotating said wheel in the same direction and at such relative speeds that the conveyed canes are rolled along and pressed against the said cutting edge in sequence to score each cane along a circumferentially extending line while a bending moment of increasing magnitude is applied thereto to cause a square break in the cane at the score line.

2. A machine for subdividing vitreous canes comprising in combination, a conveyor for carrying a plurality of canes in spaced parallel positions along a circular path while supporting the canes for rotation on their longitudinal axes, a stationary knife presenting to the outer sides of the conveyed canes a straight cutting edge intersecting the circular path of the conveyed canes in a plane normal to the axes of the canes, a wheel mounted for rotation on an axis parallel with the axes of the conveyed canes and opposed to and spaced from the said cutting edge a distance less than the diameter of the conveyed canes for engaging and rolling the canes along said cutting edge, said wheel being stifiiy resilient at its peripheral portion, the stifi'ly resilient peripheral portion of said wheel extending parallel with the axes of the conveyed canes so as to en gage the said canes for a substantial distance longitudinally of the canes, said cutting edge being positioned to engage the conveyed canes intermediate the ends of the longitudinally extending portions of the canes engaged by the stifily resilient peripheral portion of said wheel, said machine comprising also means for driving said conveyor and for rotating said Wheel in the same direction and at such relative speeds that the conveyed canes are rolled along and pressed against the said cutting edge in sequence to score each cane along a circumferentially extending line while a bending moment of increasing magnitude is applied thereto to cause a square break in the cane at the score line.

References Cited in the file of this patent UNITED STATES PATENTS 1,123,336 Madden Jan. 5, 1915 1,482,206 Tuley Jan. 29, 1924 1,754,143 Brown et al. Apr. 8, 1930 1,951,140 Fahrney Mar. 13, 1934 2,504,655 Dallas Apr. 18, 1950 2,553,136 Eisler May 15, 1951 FOREIGN PATENTS 469,215 Germany Dec. 7, 1928 

